Compiled by Twilightoutside from the Definitive Challenges List, who thought it would be handy to have a complete list for each version of the game, and I agree.

(Note: I did not think it necessary to include any lost challenges here, but they are still included in the Definitive Master Challenge List here. If you created a challenge that we classified as LOST and want to update it, send a PM to Lorinsv and I will add your challenge to the appropriate list.)